Cannot access additional web cams on the Vive

Hi,

We would like to show what is on the web cam on a Vive. Note we are not using the web cam on the vive, but a different web cam that is attached to the computer.
When the Vive starts, we cannot get access to any other webcams. ( And can't get access to the vive one either)

I can access the web cam provided the Vive is not present. I am using Steam VR.
The error is "Could Not Connect pins". I have tried rebooting, disabling the vive web cam, etc.